Green-blue tetrazo dye.



UNITED STATES PATENT OFFICE.

JULIUS HERBABNY, OF OFFENBACH-ON-THE-MAIN, AND CHRISTOPH HARTMANN, OF FRANKFORT-ON-THE-MAIN, GERMANY.

GREEN-BLUE TETRAZQ DYE.

SPECIFICATION forming part of Letters Patent N 0. 639,040, dated December 12, 1899.

Application filed September 28, 1898- Serial No. 692,074. (Specimens-l To all whom it may concern:

Be it known that we, JULIUS HERBABNY, doctor of philosophy, residing at Offenbachon-the-Main, and OHRIsToPH HARTMANN, doctor of philosophy, residing at Frankforton-the-Main, Germany, have invented a new Greenish-Blue Tetrazo Dyestufr", of which the following is a specification.

This invention consists in a new substantivepoly-azo-coloring matter suitable fordyeing nnmordanted cotton and obtainable by the reduction of the disazo dyestulf which results from the combination of a toluylenediamin-sulfoacid,

CH N11,: N11,: SO H:

(1:2:6z4); (l:2:4:5); (1:8:4z6),

with two molecules of para-nitro-diazo-benzenechlorid, tetrazotizing the thus-obtained tetraamido-disazo dyestuff with two molecules sodium nitrite, and finally combining with two molecules of a suitable component.

The following example illustrates the manner in which our invention may be carried out and brought into practical effect. The parts are by weight. Combine in a weaklyalkaline solution twenty-two and two-fifths (22.45) parts of toluylene dianiiu sulfoacid (sodium saltlwith twenty-seven and threefifths (27 .6) parts of paranitranilin,diazotized, as usual, withthirteen and four-fifths (13.8) parts of sodium nitrite, and reduce the precipitated dyestuff with about one hundred and twenty (120) parts of sodium sulfid in an aqueous solution at'about fifty to ninety degrees centigrade, (-90 G.) The end of the reaction is recognized when the color of the mixture does not change any more. Then precipitate in the cold the product of the reduction by acids, avoiding any excess of acid, and purify by redissolving in soda, exactly neutralizing with acids. Then diazotize in hydrochloric -acid solution, while cooling, twenty-three (23) parts of the thus-obtained tetraamidodisazo body with seven (7) parts of sodium nitrite and combine the resulting reddish-brown tetrazo compound with thirtyfive (35) parts of the amidonaphthol disulfoacid H, adding as much soda as to keep alkaline the final reaction, and precipitate with common salt. The dyestuff thus obtained dyes uumordanted cotton from alkaline or neutral baths greenish blue and forms a grayblack to black powder, insoluble in alcohol, soluble in water with a pure-blue shade,which does not change on addition of soda, butturning into a bluish violet on adding acids. It is also soluble in concentrated sulfuric acid, givingapure-bl ue solution,wl1icl1 after standing for some time or on addition of water turns into violet to reddish violet.

Now what We claim is As a new article of manufacture, the greenish-blue tetrazo dyestuff, obtainable by the combination of the tetraamido disazo compound derived from a toluylenedianiinsulfoacid and para-nitrodiazobenzene with amidonaphtholdisnlfoacid H which hasthe formula SO Na SO Na 6 5 2 g H some 06 mi, 3 OH N:N o,H,-N:N 2 N=NCGH1N:N\ s N CwHs so na and is a grayish-black to black powder insoluble inalcohol, is soluble in Water with a pureblue shade which does not change on addition of soda but tn rns into a bluish violet on adding acids, is also soluble in concentrated sulfuric acid giving a pure-blue solution which after standing for some time or on addition of water turns into violet to reddish violet, and yields on unmordanted cotton in alkaline or neutral baths greenish blue shades, fast to washing, all substantially as herein described. In testimony whereof we have signed our names to this specification. in the presence of two subscribing witnesses.

. JULIUS HERBABNY.

OHRISTOPH HARTMANN. Vitnesses:

DEAN B. MASON,

JEAN GRUND. 

